scholarly journals On the Issue of Assessing the Ecological State of Various Watercourses in the Conditions of Anthropogenic Pressure.

2021 ◽  
pp. 106-120
Author(s):  
Keyword(s):  
Water Pollution ◽  
Organic Matter ◽  
Desirability Function ◽  
Negative Relationship ◽  
Principal Component ◽  
Small Rivers ◽  
High Water Content ◽  
Anthropogenic Pressure ◽  
Ecological State

An assessment is given of the ecological state of nine rivers with different levels of anthropogenic load related to the Volga, the Don and the Ural basins. The water quality was assessed on the basis of several indices: the widely used specific combinatorial water pollution index (SCWPI), and statistical criteria based on the data of long-term environmental monitoring: the plasticity indicator as a measure of ecosystem sustainability and the desirability function. Hydro/chemical studies included indicators of oxygen regime, salt composition, organic matter, biogenic and toxic elements. The calculated SCWPI fluctuated in the range of 3,0–5,4, which corresponds to the quality category “very polluted” - “dirty”. The water of the lowest quality is in the small rivers Berezina and Elshanka, part of which is located in the industrial zone of the city of Saratov. The greatest contribution to the assessment of the degree of water pollution is made not only by the concentration of technogenic metals, but also by indicators of the content of organic matter, the amount of which depends on the level of bioproduction processes. The principal component analysis made it possible to structure the indices calculated for each river and to “explain” some of the information contained in the initial variables. Two main components were selected, based on the analysis results. The first factor integrates a negative relationship between the value of the UCIPI and the length of the river. Large rivers are more resistant to pollution due to their high water content. The second factor incorporated environmental criteria - the desirability function and the plasticity indicator, i.e. statistical indicators based on the data of long-term hydro/chemical monitoring and taking into account the real ecological state ̶ "health" of natural water systems and their sustainable functioning. Cluster analysis of the obtained statistical indices made it possible to divide the studied rivers by the quality of the aquatic environment into 4 groups.

scholarly journals Long-Term River Water Quality Trends and Pollution Source Apportionment in Taiwan

Water ◽  
2018 ◽  
Vol 10 (10) ◽  
pp. 1394 ◽  
Author(s):  
Marsha Putri ◽  
Chao-Hsun Lou ◽  
Mat Syai’in ◽  
Shang-Hsin Ou ◽  
Yu-Chun Wang
Keyword(s):  
Water Pollution ◽  
Water Quality ◽  
Heavy Metal ◽  
Cluster Analysis ◽  
River Water ◽  
Principal Component ◽  
Pollution Level ◽  
Metal Levels ◽  
Metal Monitoring

The application of multivariate statistical techniques including cluster analysis and principal component analysis-multiple linear regression (PCA-MLR) was successfully used to classify the river pollution level in Taiwan and identify possible pollution sources. Water quality and heavy metal monitoring data from the Taiwan Environmental Protection Administration (EPA) was evaluated for 14 major rivers in four regions of Taiwan with the Erren River classified as the most polluted river in the country. Biochemical oxygen demand (6.1 ± 2.38), ammonia (3.48 ± 3.23), and total phosphate (0.65 ± 0.38) mg/L concentration in this river was the highest of the 14 rivers evaluated. In addition, heavy metal levels in the following rivers exceeded the Taiwan EPA standard limit (lead: 0.01, copper: 0.03, and manganese: 0.03) mg/L concentration: lead-in the Dongshan (0.02 ± 0.09), Jhuoshuei (0.03 ± 0.03), and Xinhuwei Rivers (0.02 ± 0.02) mg/L; copper: in the Dahan (0.036 ± 0.097), Laojie (0.06 ± 1.77), and Erren Rivers are (0.05 ± 0.158) mg/L; manganese: in all rivers. A total 72% of the water pollution in the Erren River was estimated to originate from industrial sources, 16% from domestic black water, and 12% from natural sources and runoff from other tributaries. Our research demonstrated that applying PCA-MLR and cluster analysis on long-term monitoring water quality would provide integrated information for river water pollution management and future policy making.

scholarly journals Variation of soil organic matter depends on light-fraction organic matter under long-term monocropping of different crops  

2021 ◽  
Author(s):  
Futao Zhang ◽  
Yunfa Qiao ◽  
Xiaozeng Han ◽  
Bin Zhang
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Principal Component ◽  
Light Fraction ◽  
Bulk Soil ◽  
Density Fractions ◽  
Chemical Structures ◽  
Light Fraction Organic Matter ◽  
The Difference

Cultivating crops influences soil organic matter (SOM), but the effect of different crops remains unclear, particularly under long-term monocropping. The objective of this study was to identify how different crops influence the content and chemical structures of SOM under long-term monocropping. Here, soils were sampled (0–20 cm) under 27-year soybean and maize monocropping and separated into different physical fractions. The content and chemical structures of SOM in all fractions were determined. SOM contents were higher under soybean than maize in bulk soil and macroaggregates and their light-fractions instead of microaggregates and silt and clay. The difference in SOM chemical structure was observed in aggregates and density fractions rather than bulk soils and supported by the result of principal component analysis. The proportion of O-alkyl C in macro- and microaggregates and all free light fractions and that of aromatic C in mineral-associated fractions were higher, while that of carbonyl C was lower under maize than soybean. These results demonstrated that different crops monocropping influences the content and chemical structures of SOM, and the variations were mainly in the light-fraction SOM and highlight a higher sensitivity of physical fractions than bulk soil to different crops.  

scholarly journals Long-Term Studies Of Surface-Sediment Diatom Assemblages In Assessing The Ecological State Of Lake Ladoga, The Largest European Lake

2021 ◽  
Vol 14 (1) ◽  
pp. 251-262
Author(s):  
Anna V. Ludikova
Keyword(s):  
Surface Sediment ◽  
Lake Ladoga ◽  
Anthropogenic Pressure ◽  
Ecological State ◽  
Diatom Assemblages ◽  
Ecosystem Recovery ◽  
Phytoplankton Communities ◽  
The 1960S ◽  
Ecosystem State

The study continues a series of observations started in the late 1950s, aimed at inferring changes in the Lake Ladoga ecosystem state recorded in the surface-sediment diatom assemblages. At the pre-anthropogenic stage (prior to the 1960s), the composition of the surface-sediment diatom assemblages indicated an oligotrophic state of Lake Ladoga. With the increased P load to the lake (late 1960s–1980s), the transition to a mesotrophic state was recorded via increased proportions of eutrophic species and decreased abundances of the taxa typical of the pre-anthropogenic stage. In the early 1990s, the composition of the surface-sediment diatom assemblages still indicated a mesotrophic state despite a decreased external P load. At the present de-eutrophication stage of Lake Ladoga (the 2000s), the abundances of eutrophic taxa steadily decrease while some taxa typical of the pre-anthropogenic period return to their dominating position in the surface-sediment diatom assemblages. However, despite the decreased P concentrations, the Lake Ladoga ecosystem has not returned to its pre-anthropogenic state as indicated by the present-day composition of the surface-sediment diatom assemblages. This suggests a delayed ecosystem response to the decreased anthropogenic pressure, and possibly some irreversible changes resulting from the eutrophication. At present, de-eutrophication processes and ecosystem recovery are superimposed upon the recent climatic changes that govern the onset and duration of the vegetative seasons for the phytoplankton communities in Lake Ladoga. The diatom-inferred changes in the ecological state of Lake Ladoga are in agreement with the results of longterm hydrochemical and hydrobiological studies.

Selective statistical estimates of multi-year monthly concentrations of biogenous pollution of small rivers of the Northwest zone of the Russian Federation

2020 ◽  
pp. 9-13
Author(s):  
Sergey Kovalenko
Keyword(s):  
Statistical Processing ◽  
Point Of View ◽  
Small Rivers ◽  
Statistical Parameters ◽  
Monthly Data ◽  
Statistical Estimates ◽  
Scientific Task ◽  
The Russian Federation ◽  
Agricultural Areas

The management of surface watercourses is an urgent scientific task. The article presents the results of statistical processing of long-term monthly data of field observations of hydrological and hydrochemical parameters along the Upper Yerga small river in the Vologda region. Sampling estimates of statistical parameters are obtained, autocorrelation and correlation analyzes are performed. The limiting periods from the point of view of pollution for water receivers receiving wastewater from drained agricultural areas are identified.

Risk Attitude and Corporate Investment under Output Market Uncertainty: Evidence from The Mekong River Delta, Vietnam

2016 ◽  
pp. 59-70
Author(s):  
Ninh Le Khuong ◽  
Nghiem Le Tan ◽  
Tho Huynh Huu
Keyword(s):  
Negative Relationship ◽  
Risk Attitude ◽  
Business Strategies ◽  
Risk Averse ◽  
Market Uncertainty ◽  
Firm Investment ◽  
Output Market ◽  
The Impact ◽  
The Relationship

This paper aims to detect the impact of firm managers’ risk attitude on the relationship between the degree of output market uncertainty and firm investment. The findings show that there is a negative relationship between these two aspects for risk-averse managers while there is a positive relationship for risk-loving ones, since they have different utility functions. Based on the findings, this paper proposes recommendations for firm managers to take into account when making investment decisions and long-term business strategies as well.

The Issue of Plastic and Microplastic Pollution in Soil

2019 ◽  
Vol 56 (3) ◽  
pp. 484-487 ◽  
Author(s):  
Valentina Constanta Tudor ◽  
Dorina Nicoleta Mocuta ◽  
Ruxandra Florina Teodorescu ◽  
Dragos Ion Smedescu
Keyword(s):  
Water Pollution ◽  
Organic Matter ◽  
Soil Pollution ◽  
Aquatic Environment ◽  
Negative Impact ◽  
Plastic Material ◽  
Soil Biota ◽  
Toxic Substances

Soil pollution with plastics represents a great threat to plants, animals, but especially to humans, as a very small quantity of the plastic which is discarded daily is recycled or incinerated in waste facilities, much of it reaching landfills where their decomposition lasts up to 1000 years and during this time the toxic substances penetrate the soil and the water. If, initially, the pollution with plastics has been identified and recognized in the aquatic environment, recent studies show that plastics residues exist in huge quantities in the soil. The present study focuses on the analysis of factors that pollute soil, so the various studies that have been carried out claim that soil pollution with plastic is much higher and increases in an aggressive manner, being estimated to be 4 to 23 times higher than water pollution with plastics, and the accumulation of microplastics in the soil has a negative impact on soil biota. Thus, once the plastic material accumulates in the soil, it is assimilated to organic matter and the mineral substitutes of the soil and persists for several hundred years.

scholarly journals Impacts of long-term plant residue management on soil organic matter quality, Pseudomonas community structure and disease suppressiveness

2019 ◽  
Vol 135 ◽  
pp. 396-406 ◽  
Author(s):  
Bryony E.A. Dignam ◽  
Maureen O'Callaghan ◽  
Leo M. Condron ◽  
Jos M. Raaijmakers ◽  
George A. Kowalchuk ◽  
...  
Keyword(s):  
Organic Matter ◽  
Community Structure ◽  
Soil Organic Matter ◽  
Residue Management ◽  
Plant Residue ◽  
Organic Matter Quality ◽  
Soil Organic Matter Quality

scholarly journals Impact of aquaculture on distribution of dissolved organic matter in coastal Jeju Island, Korea, based on absorption and fluorescence spectroscopy

2021 ◽  
Author(s):  
Jeonghyun Kim ◽  
Yeseul Kim ◽  
Sung Eun Park ◽  
Tae-Hoon Kim ◽  
Bong-Guk Kim ◽  
...  
Keyword(s):  
Organic Matter ◽  
Organic Carbon ◽  
Fluorescence Spectroscopy ◽  
Dissolved Organic Matter ◽  
Coastal Water ◽  
Coastal Region ◽  
Principal Component ◽  
Distribution Patterns ◽  
Organic Pollution ◽  
Jeju Island

AbstractIn Jeju Island, multiple land-based aquafarms were fully operational along most coastal region. However, the effect of effluent on distribution and behaviours of dissolved organic matter (DOM) in the coastal water are still unknown. To decipher characteristics of organic pollution, we compared physicochemical parameters with spectral optical properties near the coastal aquafarms in Jeju Island. Absorption spectra were measured to calculate the absorption coefficient, spectral slope coefficient, and specific UV absorbance. Fluorescent DOM was analysed using fluorescence spectroscopy coupled with parallel factor analysis. Dissolved organic carbon (DOC) and total dissolved nitrogen (TDN) were measured using high-temperature catalytic oxidation. The DOC concentration near the discharge outlet was twice higher than that in natural groundwater, and the TDN concentration exponentially increased close to the outlet. These distribution patterns indicate that aquafarms are a significant source of DOM. Herein, principal component analysis was applied to categorise the DOM origins. There were two distinct groups, namely, aquaculture activity for TDN with humic-like and high molecular weights DOM (PC1: 48.1%) and natural biological activity in the coastal water for DOC enrichment and protein-like DOM (PC2: 18.8%). We conclude that the aquafarms significantly discharge organic nitrogen pollutants and provoke in situ production of organic carbon. Furthermore, these findings indicate the potential of optical techniques for the efficient monitoring of anthropogenic organic pollutants from aquafarms worldwide.

scholarly journals Higher Temperatures Decrease Fruit Size in Strawberry Growing in the Subtropics

Horticulturae ◽  
2021 ◽  
Vol 7 (2) ◽  
pp. 34
Author(s):  
Christopher Menzel
Keyword(s):  
Fruit Size ◽  
Negative Relationship ◽  
Titratable Acidity ◽  
Fruit Weight ◽  
Soluble Solids ◽  
Marketable Yield ◽  
Significant Relationships ◽  
Small Fruit ◽  
Solids Content

Five strawberry (Fragaria × ananassa Duch.) cultivars were grown in Queensland, Australia to determine whether higher temperatures affect production. Transplants were planted on 29 April and data collected on growth, marketable yield, fruit weight and the incidence of small fruit less than 12 g until 28 October. Additional data were collected on fruit soluble solids content (SSC) and titratable acidity (TA) from 16 September to 28 October. Minimum temperatures were 2 °C to 4 °C higher than the long-term averages from 1965 to 1990. Changes in marketable yield followed a dose-logistic pattern (p < 0.001, R2s = 0.99). There was a strong negative relationship between fruit weight (marketable) and the average daily mean temperature in the four or seven weeks before harvest from 29 July to 28 October (p < 0.001, R2s = 0.90). There were no significant relationships between SSC and TA, and temperatures in the eight days before harvest from 16 September to 28 October (p > 0.05). The plants continued to produce a marketable crop towards the end of the season, but the fruit were small and more expensive to harvest. Higher temperatures in the future are likely to affect the economics of strawberry production in subtropical locations.

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